"Carl was my friend. In all the years that I knew him I never had a cross word with him. For 14 years we worked together.

"He was a great chief whip and a minister who served his country with distinction."

The First Minister insisted he and his staff would co-operate in full with the inquest into Mr Sargeant's death and admitted that an independent investigator may have to probe his own behaviour.

But he denied any wrongdoing in the case, telling reporters: "I quite properly did all that I could to make sure that everything was being done by the book.

"I had no alternative but to take the action that I did and I hope that people will understand that."

Mr Jones, who appeared close to tears during his statement, concluded: "These are the darkest days any of us can remember in this institution – but they are darkest of all for the family, and we must respect their right to grieve in peace at this time.”

He left the conference hastily without taking any questions from the media.

Mr Sargeant, a member of the Welsh Assembly, with his wife and children

Alun Michael, the former First Minister who also served in the Cabinet under Tony Blair, said today that Mr Jones has questions to answer.

He told BBC Radio 4: "I hope it will become clearer what the allegations were and why it was that the matter was referred to the Labour party to deal with.

"I hope that the family will have the response that they are understandably seeking - what were the allegations and why were they not shared with Carl, as the person who was under criticism, and why was the support not given and who should have given it?

"The problem for everybody - family, friends, people involved in the wider public life in Wales - is that we don't know what this is all about."

The First Minister spent hours today talking to other Labour members of the Welsh Assembly behind closed doors in Cardiff today.

Mr Sargeant's friend Daran Hill expressed "disbelief" at Mr Jones's decision to talk to colleagues before giving a public statement or contacting the grieving family.